UefiCpuPkg/MpInitLib: Check APIC mode change around AP function

[mirror_edk2.git] / UefiCpuPkg / Library / MpInitLib / MpLib.c

diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.c b/UefiCpuPkg/Library/MpInitLib/MpLib.c
index 735e099b32f28e934ca20603679574bf82a02a30..c6f81914d27a2a04fd86909d03b5180977d922cc 100644 (file)
--- a/UefiCpuPkg/Library/MpInitLib/MpLib.c
+++ b/UefiCpuPkg/Library/MpInitLib/MpLib.c
@@ -547,6 +547,7 @@ ApWakeupFunction (
   volatile UINT32            *ApStartupSignalBuffer;\r
   CPU_INFO_IN_HOB            *CpuInfoInHob;\r
   UINT64                     ApTopOfStack;\r
+  UINTN                      CurrentApicMode;\r
 \r
   //\r
   // AP finished assembly code and begin to execute C code\r
@@ -560,6 +561,7 @@ ApWakeupFunction (
   ProgramVirtualWireMode ();\r
   SyncLocalApicTimerSetting (CpuMpData);\r
 \r
+  CurrentApicMode = GetApicMode ();\r
   while (TRUE) {\r
     if (CpuMpData->InitFlag == ApInitConfig) {\r
       //\r
@@ -627,11 +629,23 @@ ApWakeupFunction (
             ApStartupSignalBuffer = CpuMpData->CpuData[ProcessorNumber].StartupApSignal;\r
             CpuInfoInHob[ProcessorNumber].ApTopOfStack = CpuInfoInHob[CpuMpData->NewBspNumber].ApTopOfStack;\r
           } else {\r
-            //\r
-            // Re-get the CPU APICID and Initial APICID\r
-            //\r
-            CpuInfoInHob[ProcessorNumber].ApicId        = GetApicId ();\r
-            CpuInfoInHob[ProcessorNumber].InitialApicId = GetInitialApicId ();\r
+            if (CpuInfoInHob[ProcessorNumber].ApicId != GetApicId () ||\r
+                CpuInfoInHob[ProcessorNumber].InitialApicId != GetInitialApicId ()) {\r
+              if (CurrentApicMode != GetApicMode ()) {\r
+                //\r
+                // If APIC mode change happened during AP function execution,\r
+                // we do not support APIC ID value changed.\r
+                //\r
+                ASSERT (FALSE);\r
+                CpuDeadLoop ();\r
+              } else {\r
+                //\r
+                // Re-get the CPU APICID and Initial APICID if they are changed\r
+                //\r
+                CpuInfoInHob[ProcessorNumber].ApicId        = GetApicId ();\r
+                CpuInfoInHob[ProcessorNumber].InitialApicId = GetInitialApicId ();\r
+              }\r
+            }\r
           }\r
         }\r
         SetApState (&CpuMpData->CpuData[ProcessorNumber], CpuStateFinished);\r